Quill inconsistent spacing between line breaks, headers, code, etc.
Headers appear to only have 5px spacing, but a full line break is 15px. This doesn't look great:
http://i.venner.io/2018-09-23_14-14-33.webm
Code blocks have 5px margin-top and margin-bottom, which causes bad balancing between any preceding and following line breaks, as seen here:
This example shows that the line break above the code block has margin-bottom 15px, but because the code block's margin-bottom is only 5px, the spacing is unbalanced.